Continuously variable transmission



Sept. 2 7, '1938.

J. O. ALMEN ET AL CONTINUOUSLY VARIABLE TRANSMISSION 6 Sheets-Sheet 1*.

Filed Feb. 3, 1932 Sept. 27, 1938. J. o. ALMEN E-r An. v 2,131,158'

CONTINUOSLY VARIABLE TRANSMISSION Filed Feb. 3, 1932 e sheets-sheet 2 iM/venten prr 0. dlmezz 0,. O G RNON www.,

Sept. 27, 1938.- .1, o. ALMEN'ET 1. 2,131,158

CONTINUOUSLY VARIABLE TRANSMI SS ION @wir A www Sept. 27,- 1938.. J. o. ALMEN ET A1.l

CONTINUOUSLY VARIABLE TRANSMISSION Filed Feb. 5, 1932 e sheets-sheet 4 IlI 45.1 uw v snmmw 1 .1 a y Sept. 27, 1938. .J. o ALMEN ET AL IGONTINUOUSLY VARIABILE TRANSMISSION' Filed Feb. 3, 1932 6 Sheets-Sheet 5' Sept. 27, 1938. J. o. ALMEN` ET A1, 2,131,158 i i CONTINUOUSLY VARIABLE TRANSMISSION I Filed Feb. s, 1932 e sheets-sheet e Patented Sept. 27, 1938 CONTINUOUSLY VARIABLE TRANSMISSION John 0. Almen, Royal Oak, and Jacob Ehrlich,

Detroit, Mich., assignors, by mesnc assignments, to General Motors Corporation, Detroit, Mich., a corporation of Delaware Application February 3, 1932, Serial No. 590,534

59 Claims. A (Cl. 'I4-190.5)

This invention relates to variable speed ratio transmission mechanism, comprising a plurality of races having toroidal raceways and interposed friction rollers, particularly designed to 5 be installed in a motor vehicle to'transmit the power ,of an internal combustionengine to the traction Wheels.

Objects of the invention are, in general, to

improve the performance of friction transmisl sion mechanisms and to achieve accuracy and ease of control, specifically attained in part by:

(l) Facilitating changing the direction of ro-` tation of the power output shaft of the transmission with respect to that of the power input l shaft therefor in changing from forward to reverse drive, and, incidentally, placing the transmission in neutral, that is disconnecting both forward and reverse drive trains without otherwise disengaging the engine from the trans- 20 mission;

(2) Adjusting the degree of tractive pressure between races and interposed rollers in accordance with the load upon the output shaft without angularly displacing the races keyed to the output shaft relatively to one another or to the shaft; p

(3) Controlling the speed ratio by externally derived ratio-changing effort imparted to one only of the intermediate transmission rollers (a control or master roller), thereby easing materially the control effort compared with that required if applied to all of the intermediate rollers, and avoiding the necessity of using servo mechanism to effect ratio change; 35 (4) Utilizing the torque forces mutually exerted between races and intermediate friction rollers to equalize the torque transmitted by the' several rollers, and, as a corollary, causing all of the rollers to assume equivalent ratio posi- 40 tions in response to said torque forces after one (the master roller) has been forced outof its norma1`plane of rotation and its axis displaced from the radial plane that includes the main axis of the transmission and the roller center 45 by an external effort of control;

(5) Causing automatic displacement of the rollers, other than the master roller, .in their normal planes of rotation so as to displace their axis of rotation in response to ratio changing or 0 tilting movement of the master roller in order that the torque forces acting mutually during rotation on the races and said other rollers may cause all rollers to assume a corresponding ratio plied thereto radially outward of its perimeter, about a line connecting its points of contact with the races in order to displace its axis out of the radial plane including the main axis and roller l center for initiating change of ratio or tilt position;

('7) Causing the master roller in tilting or changing its paths of contact with toroidal raceways automatically to assume a position in which its axis of rotation is restored to said radial plane after it has been displaced from said plane by inclining the roller;

(8) Automatically adjusting the connections between the master roller and the external control means soA that the ratio changing effect of external force applied to 'the controlled roller will be the same for both forward and reverse drives:

(9) Limiting the ratio changing rate of all rollers by limiting the extent of inclination that can be imparted to the'master roller in a given time; e

(10) Varying the permissible rate of ratio changing or tilting movement of the friction rollers in accordance with the ratio or tilt position thereof at time of application of ratio changing effort;

(11) Automatically governing the transmission ratio in accordance with the speed of the power input shaft of thevfriction transmission mechanism;

(12) Starting circulation of the lubricating oil immediately when the engine is started, transmission power input shaft coupled thereto, and transmission in neutral, to the end that the friction transmission elements may be well lubricated prior to starting the car.

The aforesaid objects, and others, are attained by means of the combination of a frictiontransmission unit with a selectivel gear transmission unit arranged in series within a housing, the selective gear unit being disposed between the friction unit and the source of power, as hereinafter described and illustrated in the -attached drawings; and by means of the several combinations of elements, sub-combinations, and details of construction and arrangements to be specifically described.

The friction transmission unit comprises, generically, an output shaft having a race with toroidal raceways keyed to each end, a race with opposite toroidal raceways intermediate said end racesv coaxial with said output shaft but supported independently of. it on a shaft-surrounding bearing fixed to the housing, and intermediate friction rollers in tractive engagement with the raceways.

'I'he selective gear transmission unit comprises, generically, an input shaft in axial alinement with said output shaft to which said intermediate race is coupled, countershaft, forward and reverse drive trains, and selective controls whereby the transmission may be coupled to the engine to transmit drive in forward or reverse, or may be adjusted to a neutral condition so that no power is transmitted therethru.

Within the housing, associated with the selective gear unit, are disposed a governor, driven only when the car is in motion, adapted to control the speed-ratio of the friction unit, and a lubricating pump adaptedto start circulation of lubricating oil prior to starting the car.

Associated with the friction unit are spring and torque loading devices adapted to apply pressure toy the races in such manner as to secure tractive engagement of the rollers therewith in accordance with the load, wherein a power transmitting coupling on the delivery end of the output shaft has a lost motion driving connection thereto and is associated with wedging or camming devices operative to translate any angular movement of the coupling into an axial movement of an adjacent race.

The intermediate friction rollers are positioned and supported by spider arms fixed to a floating tube which surrounds the output shaft and may float laterally and axially in response to unbalanced torque forces applied between rollers and races` The floating sleeve is centered by spring devices and its movements are damped by dash pots supplied with oil from the lubricating system.

'Ihe ends of the roller positioning spider arms and the bearings of said rollers have 'mutually reacting devices in the form of inclined planes whereby movements of the floating tube caused by inequalities of torque load upon the several rollers tend to effect a readjustment of the rollers in such manner as to equalize the loads. One of the rollers is so mounted as to be steered to new ratio or tilt positions by rocking or inclining it about an axis joining its points of contact with the races. trol or master roller and it may be inclined by externally applied effort, Whether it is rotating in one sense or the opposite, thru a control yoke which assumes different angular positions with respect to a plane normal to the race axis including the roller center in accordance with the sense of rotation. The other rollers are automatically displaced by a translatory movement in their planes of rotation so that their axes are displaced from a-radial plane including the main axis and the roller center, in order that the inherent torque forces exerted during rotation may cause suitable readjustment of ratio position.

Said control yoke, which is pivoted to the masl ter roller trunnion and has a friction bearing upon one or both faces of the master roller is thereby urged to swing to one side or the other of a plane normal to the race axis including the roller center to a limited extent, according to the direction of rotation of the roller, whereby pressure properly applied to the outer extremity of the yoke will so incline the roller and displace its axis of rotation that, as it tilts to a new ratio position, the axis of rotation will be returned to the radial plane in which it normally lies.

External force is applied to the master roller for ratio changing purpose thru a ,T shaped rock This roller is herein termed the conlever having a slot in the/T head or cross arms arranged to engage said automatically adjustable control yoke in either of its adjusted positions so that the same directions of movement imparted externally to the rock lever will adjust the inclination of the master roller to cause increase or decrease of speed-ratio by the same movements whether the transmission be coupled in forward or reverse gear.

The axis of said rock lever is parallel with and displaced slightly with respect to a line passing thru the center of the roller, normal to a plane that includes the race axis and the roller center. The end of the control yoke consists of a parallel sided platen having centrally disposed rounded bearings projecting from opposite sides, the distance from bearing point to bearing point thru the platen being equal to the width of the slot in the head, thus providing clearance space between the rest of the platen and the opposite sides of the slot in the lever. 'I'his disposition of the axis of the rock lever thus provides for variation of degree of inclination imparted to the roller in different ratio or tilt positions by a rocking movement of the lever.

Other features embodied in the invention are specifically set forth hereinafter.

It will be understood that in friction transmissions of the type herein disclosed power is transmitted in parallel from or to the central race (or races) to or from the end races, drivingly secured to the concentrically disposed power output shaft, thru the two sets of friction rollers in tractive contact with the races. When the plane of rotation of a roller, (that is, the plane normalto the axis of rotation of the roller) passing thru thepoints of contact of the roller with the races, is perpendicular to a plane including the axis of the races, and the axis of rotation of the roller lies in said plane, the torque forces are in balance and the rollers 'tend to maintain their normal positions. When the plane of rotation of a roller is parallel with the race axis the ratio is 1:1. When it is tilted or non-parallel with the race axis the ratio is either greater or less than 1:1.

If a roller be inclined, i. e., rocked about an axis joining its points of contact with the races, so as to incline the axis of rotation out of said axial plane the torque forces are unbalanced and the roller thereupon tilts-i. e. changes the f angle of its plane of rotation with respect to the main axis. Likewise any movement imparted to a roller that displaces its axis of rotation vout of said axial plane brings to bear upon it unbalanced torque forces which cause it to tilt to a. different ratio position.

Should the axis of rotation of a roller be displaced out of the axial plane that normally includes it, the roller would tend to spiral on the races until it ran. oi or its spiraling-movement was checked, unless some means were provided for returning the axis of rotation into said axial plane. The act of bringing back the axis of rotation of a roller to said axial vplane after it has once been displaced is herein termed restoration. Means for effecting restoration is hereinafter described. n

In the accompanying drawings wherein the lsame reference characters indicate like parts Fig. 2 is a plan view of the housing and transmission mechanism disclosed in Fig. 1 viewed in the direction of the arrows `2-2 Fig. 1, parts of the housing having been broken away to expose enclosed mechanisms;

Fig. 3 is a diagram of a fragment of a journal piece for the control roller of the friction set;

Fig. 4 is a view in elevation of the transmission viewed from the right hand side, or side opposite that from which Fig. 1 is viewed, the housing having been broken away in part to expose enclosed mechanism;

Fig. 5 illustratesa transverse section on the planes indicated by the line 5-5 of Fig. 1 exposing the parts that would be seen viewe-d in the direction of the arrows, that is, rearward;

Fig. 6 is a. detail view of a governor-driving gearing taken on the plane indicated by line 6 5 means for coupling the transmission mechanism in the direct or reverse trains at will, taken on line 'l-'l of Fig. 5;

Fig. 8 illustrates a section, on the plane indicated by line 8 8 of Fig. 4, thru a means for regulating the speed-ratio changing mechanism;

Fig. 9 illustrates a transverse section on the plane indicated by line 9 9 in Fig. 1, the exposed parts being viewed in the direction of the arrows, that is, in a forward direction;

Fig. 10 is a view of the master or speed-ratio controlling friction roller assembly the parts of the assembly having been disassembled an'd separated;

Fig. 11 is a diagram showing the relation of the races and intermediate friction rollers and the mountings of the latter on floating spider arms;

Fig. 12 is a diagram illustrative of the mode of operation of the mechanism for automatically equalizing the torque transmitted by the several rollers of one set, and

Figs. 13, 13a and 13b are diagrams illustrative of the mode of operation of an externally operated rock lever for inclining the master. roller and limiting the degree of inclination that can be imparted to said roller.

A housing, indicated as an entirety in the drawings byreference letter H, encloses and supports the variable speed mechanism of this invention, which is designed to be disposed between an engine and propeller shaft of a motor vehicle. A relatively large compartment 20, houses a shaft connected at its rear end to the propeller shaft, friction driving and driven races, friction power transmitting rollers interposed between the races, supporting means and accessories, which constitute the variable speed-ratio assembly of this transmission. For convenience of assembly of the friction elements and control parts within the compartment 20, the housing may consist of two parts divided in a transverse plane and united end to end, as by bolts 2| penetrating circumferential abutting end flanges provided on the two parts.

A smaller compartment 22 within said housing, disposed in advance of the compartment 20, en-

' closes gearing adapted to be selectively conthe front end of the housing is intended to be rigidly secured to the' usual bell housing which covers the main friction clutch for coupling and uncoupling an internal combustion engine to or from the transmission, as is usual in motor vehicles. The housing is provided with a rear transverse wall 24, an intermediate partition 25 between compartments 20 and 22, and a forward partition 26 separating compartment 22 from the compartment within bell-like housing member 23. The said partitions and wall support bearings for the main shafting sections. The housing is also provided with removable cover plates suitably located to afford convenient access to the interior of the compartments and the necessary bearing supports for movable parts of the mechanism`other than the main shaft sections. Heat disssipating ribs'may be formed o'n the housing and suitable Ventilating or breather openings therein.

Referring particularly to Fig. 1,-numeral 30 indicates a prime mover shaft such as the main clutch shaft, usual in motor vehicle transmission mechanism, the front end of which may be provided with one element of the usual main friction clutch (not shown) by which the transmission maj7 be directly coupled to or uncoupled from the engine shaft. The rearward end of main clutch shaft 30 is journaled, preferably in ball bearings 3l, in the housing partition 26; it is drilled and counterbored to receive the front end of a shaft 32, piloted, preferably, in roller bearings 33, within the counterbored cavity. The rear end of shaft 32 is journaled, preferably, in

vball bearings 34 supported in partition 25 of the housing. 'I'he rear end of shaft 32 is drilled and counterbored, like the rear end of main clutch shaft 30, for the purpose of receiving the front end of shaft 35, which is piloted within roller bearings 36 within the counterbored cavity. The rear end of shaft 35 is journaled, thru surrounding interposed parts, preferably within ball bearings 3l supported in the rear wall 24 of housing H. The primary element of the surrounding interposed parts referred to is an externally flanged nut 38 threaded tc the shaftand provided with radial spanner-engageable tongues and grooves 39 whereby it may be adjusted. Surrounding the flanged nut 38 is a universal joint yoke 40 adapted to connect shaft 35 with a propeller shaft of any usual type by which the power of the engine mayA be transmitted to the traction wheels of a vehicle. Yoke 410 has a reduced external cylindrical zone to receive the inner race of the ballr bearing 31. At its forward end it is provided with an internal flange 4I bearing upon the external surface of nut 38, while rearward of said internal flange said yoke has bearing upon the external flange 42 of nut 38. A thrust bearing 43 is interposed betweensaid flanges 4| and 42, and said yoke 40 is adapted to rotate a limited extent with respect to shaft 35, all by means to be described and for purposes to be stated hereinafter in its appropriate place. 'I'he alined axes of shafts 30, 32 and 35 constitute ,the main -axis of the transmission.l Shaft 32`is adapted to be rotated in one sense for forward driving and in the opposite sense" for reverse driving by shaft 30; shaft 35 is adapted to be driven by shaft 32 thru intermediate variable speed friction gearing to be described later. The described bearing equipment for shaft 35 is such as to permit slight axial movement of the shaft in the bearings.

Shaft 32, which may be considered the power input shaft of the' friction transmission mechanism, is adapted to be directly coupled to the main clutch shaft 30' by means of a manually controllable dog clutch. Shaft 32 is also adapted to be driven by shaft 30 in a reverse direction by means of a reversing gear train which may.

be coupled by manual effort after releasing the direct forward drive coupling by means and in a manner to be described presently. If shaft 32 be directly coupled to shaft 30, shaft 35, which may be considered the power output shaft of the friction transmission mechanism, will be rotated ln a direction to impart forward movement to the vehicle. If shaft 32 be coupled in reverse to shaft 30, shaft 35 will be rotated in a direction to impart rearward movement to the vehicle.

Referring now to Figs. 1 and 5, the direct and reverse trains will be described whereby the shaft 32 may be rotated in either the forward or reverse drive sense according to selective controlling actions of ,the/ operator. Rigid with main clutch shaft 30, at its rear end within the compartment 22, is an externally toothed gear 50, the rearward face of which is provided with a cavity bounded circumferentially by a row of internally directed gear-like teeth 5| concentric with the shaft axis, and constituting the socket element of a dog clutchu The plug element of said dog clutch is an element 52splined to slide but not rotate on the shaft 32. Element 52 is provided with external gear-like teeth 53 adapted to interlock with said internal teeth 5|. When teeth 5| and 53 are interlocked, shaft 32 must rotate in unisony with shaft 30 at the same speed and in the same direction. This is the condition of the transmission mechanism when coupled for forward driving. The external teeth of gear 50 are in constant mesh with the teeth of a gear 6U which is mounted rigidly (in this embodiment) on an externally splined sleeve 6| rotatable on a shaft 62 the ends of which are secured in suitable seats in the partitions 25 and 26. A reverse train gear 63 is slidably mounted on sleeve 6| so as to be compelled to rotate with it. The teeth of gear 63 are adapted `to be engaged with the teeth of a reverse train gear 64 rotatable about a shaft 65 the end s of which are fixed in partitions 25 and 26 of the housing H. Reverse gear 6I is in constant mesh with reverse train gear 66 which is fixed to rotate with-shaft 32. If slidable reverse gear 63 be slid rearward so that its teeth intermesh with the teeth of gear 64 on shaft 65 then the transmission is in condition to be driven rearward by means of the train consisting of gear 50 on the main clutch shaft, fixed countershaft gear 60, slidable countershaft gear 63, intermediate reverse gear 6l, and fixed gear 66 on shaft 32. Manually controllable means are present for coupling the clutch for direct drive forward, for coupling thereverse train, and for holding both clutch element 52 and slidable gear 63 in neutral or non-driving position. The construction and arrangement of this means is, of course, such that neither train can be coupled unless -the other is uncoupled.

In order that an operator may effect coupling of the direct drive train or the reverse drive train at will the transmission mechanism is equipped with manually workable shifter mechanism to be now described. As may be seen ,in Figs. 5 and 7 a slidable shift rod or rail 16 is mounted in slide bearings 1| and 12, so that it may be moved fore and aft parallel with the axis of shaft 32. Secured to the shift rod 10 is a bracket 13 integral with which is a laterally extending double yoke member having two-shifter-yoke branches 14 and 15. Branch yoke 14 engages a circumferential groove in slidable dog clutch element 52; branch yoke 15 engages a groove in slidable reverse gear 68 on the countershaft. Hence, if the shift rod 10 be moved in a forward direction from the neutral position illustrated in Figs. 1 and 7, teeth 53 of the slidable dog clutch element may be interlocked with teeth 5| of the companion dog clutch element on shaft 30 whereby shafts 30 and 32 are locked together rotatively, while slidable reverse gear 63 on the countershaft is also moved forward to a new but still idle position. If shaft 10 be moved back `to neutral and then still further rearward, slidable reverse gear 63 on the countershaft may be meshed with reverse gear 64 which, as stated, is in constant mesh with reverse gear 66 secured on shaft 32, whereby to couple the reverse train. Dog clutch element 52 then takes a new idle position rearward of neutral. For enabling shift rod 10 to be moved as described, a rock shaft 16 is journaled in a bearing bushing 11 seated'in the left hand side wall (looking forward toward the prime mover) of the compartment 22 as indicated in Figs. 2 and 5. An arm 18 is secured to the inside end of rock shaft 16, the lower end 19 of which is suitably rounded to provide a good bearing in a notch formed between lugs 80 projecting from the bracket 13. To the outside end of rock shaft 16 an arm 8| is fixed. Arm 8| is intended to be connected by means of linkage or the like to an operating lever or the like (not shown) located within convenient reach of the operator. In order to releasably latch shift rod 10 so as to hold the elements of the selective gear unit in neutral position, as shown in Figs. 1, 5 and '7, or in either forward or rearward position corresponding, respectively, to coupled forward.

drive train or rearward drive train, forward bushing 1| is provided internally with three pairs of 'tapered latching notches 62 (Fig. '7). A hole drilled diametrically thru the forward end of shift rod 10 located within said bushing 12 receives two plungers 83 each having a tapered external end adapted to interengage with any of the three pairs of latching notches 82. The plungers 83 are cupped or hollowed from their inner ends to receive opposite ends of a coiled expansion spring 84, which elastically presses the plungers outward and holds them yieldingly engaged either in the central pair of notches when the shift rod is in the position illustrated corresponding to neutral, or in the forward pair of notches when the shift rod has been moved to the position corresponding to coupled forward speed train or in the rearward pair of notches when the shift rod has been moved to the position corresponding to coupled reverse train.

The frictional variable speed-ratio assembly within compartment 20 of the housing and the means whereby the torque of power input shaft 32 is transmitted thru the frictional power transmitting elements to power-output shaft 35 will now be described.

Within compartment 20 of the housing are three axially spaced races 90, 9| and 92, Said races are concentrically mounted with respect to shaft 35, and the two end races 8| and 92 are so connected to said shaft that they are compelled to rotate therewith although there is capacity for slight relative axial movement between race `92 and the shaft. Intermediate race 90 is so mounted as to be relatively rotatable with respect to shaft 35 about its axis. Intermediate race 90 has a toroidal groove or raceway in each face and each of the races 3| and 92 has a similar toroidal groove or raceway facing the corresponding toroidal groove or raceway in race 90. In order to transmit rotary motion from the center race 90 to the end races 9| and 92, or from the latter two races to race 90, friction power transmitting rollers are interposed between race 90 and said races 9| and 92, with the treads of the rollers in tractive engagement with the toroidal raceways of the races and mounted in such manner as to prevent revolution of the rollers about the axis of shaft 35. There are two sets of transmitting rollers, and each set consists of a plurality of rollers angularly spaced one from another to af.v

In the embodiment illus-` master roller for reasons that will be made plain hereinafter. The other rollers 94 of the rearward set are follower rollers the ratio positions of which are controlled by the master roller. For convenience the master roller 94M in this embodiment occupies the uppermost position in the roller assembly, i. e. its axis of rotation lies normally in a plane that includes the race axis and is substantially vertical in the transmission as it is mounted in a. vehicle, as may be seen in Figs. 1, 2 and 9. The rollers of the forward set are controlled or non-master rollers and are indicated by numeral 95. It will be perceived that if race 90 be rotated, say in a clockwise direction, (viewed from the front of the transmission) the races 9| and 92 and in consequence the shaft 35 will rotate in the opposite or counterclockwise direction, and vice versa. In the embodiment illustrated the engine or prime mover mechanism drives the center race 90 both in forward and reverse gear couplings, so that race 90 may be deemed the driving race of the friction power transmitting assembly. Of course, whenever the vehicle over runs the engine the races 9| and 92 become the driving races and race 90 becomes a driven race transmitting the force of the coasting vehicle to the engine.

In order to transmit torque between power input shaft 32 and power output shaft 35, thru the power transmitting friction races and rollers described, said shaft 32 is positively coupled to the center race 90 by means of a coupling element.

'I'he coupling element is rigidly attached to the rearward end of shaft 32 and reaches around the periphery of race 9| to said central race 90 to which it is attached in such manner as to transmit torque thereto from said shaft 32. -This coupling may consist of a cup on bell-like device, comprising a cylinder |00, preferably having openings such as and |02, rigidly secured to a flange |03 which has a hub |04 fastened to shaft 32. At its rearward end drum |00 is keyed to the periphery of center race 90 by intercalated rectangular dogs or projections |06 and |01 (Fig. 2) formed respectively on the rear edge of coupling |00 and the rearward portion of the perimeter of race 90. A split elastic ring |05, seated in corresponding grooves in race and drum prevents relative axial movement of race and drum. 'Ihe hub |04 of fiange |03 of the couplingsupports the inner race of ball bearing 34 and also gear wheel 65,--shaft 32, coupling |00, |03, |04

One roller of the rearward set, in-

, shaft 35 as illustrated in Fig. 1.

and said inner ball bearing race being united so as to rotate together. As illustrated in Fig. 1, the forward end of hub |04 is notched or turreted, while the forward end of the hub of gear 66 is provided with corresponding inward projecting spline-like lugs engaging the notches of the hub and the grooves in shaft 32. The forward end of the hub is threaded for receiving a. fastening nut |08 which jams the gear 66 and inner race of the bearing rearward against a shoulder formed at the junction of flange |03 and its hub |04.

Central double-faced race 90 is mounted concentrically with respect to shaft 35 upon a bearing sleeve ||0 which is considerably larger than and surrounds the shaft and is -xed to the housing by means of rigid arms the outer ends of which are secured to the housing as by bolts H2.

Forward race 9| is locked to the forward end of shaft 35 to compel race and shaft to rotate together by a radial spline or rib and groove connection between the race and a flange |20 integral or otherwise made rigid with the shaft.

The rearward face of flange |20 is providedwith radial ribs or grooves, and the adjacent forward surface of race 9| is provided with mating grooves or ribs. In the drawings, Fig. 1, race 9| is shown sleeved snugly on the shaft and provided in its forward side with two diametrically alined grooves |2| .engaged by corresponding ribs on flange |20. There is, therefore, a radial spline and groove driving coupling between race 9| and shaft adapted to cause one to rotate with the l other without angular lost motion. Race 9| abuts against the rearward face of ange 20 and is kept in that position normally by the pressure of a loading device to be described which exerts force tending to maintain good tractive contact between the rollers and the races.

Race 92 is also connected to shaft 35 adjacent its rearward end so as to compel joint rotation of shaft and race without relative angular lost motion, but to permit some relative axial sliding movement. Said race is sleeved nicely on Shaft 35 is provided with splines and grooves just rearward of race 92, as indicated by numeral |30, with which a spring abutment collar,.|3| is slidably interlocked by means of'coacting splines and grooves. Collar I3| has a rearward extending hub |32 against the rear end of which bears the front end of nut 36, previously described, threaded on shaft 35. There is a radial spline and grooveinterlock between race 92 and collar |3|, ribs or splines |33 on the forward face of collar |3| engaging corresponding grooves |34 in the rearward, face of the race.

Races 9| and 92, it will be seen, are angularly immovable with respect to shaft 35 because of the described means of connecting them together, so that said races must rotate in unison without Aany relative angular displacement except as may occur by torsional flexure of 4shaft 35.

The periphery of collar |3| is provided withan vannular rabbet or seat |40, as shown in Fig. 1.

An annular, washer-like spring |4|, tapering in thickness inward from its periphery to its central orifice is sleeved on the abutment collar |3| so thatl its inner circumferential edge rests in the annular seat |40. The outer, zone of the forward face of said washer bears normally against a flat zone |42 on the rearward face of race 92. Spring |4| is normally under tension, which may be varied by rotating thenut 38. The spring |4|, therefore, in conjunction with race 92, abutesy . an axial direction and so cause disks 9| and 92' ment ring |3|, nut 38, shaft 35, ange |20 and race 9|, functions as an elastic means for maintaining a precalculated degree of tractive pressure (which may be varied by adjustment of nut 30) between the treads of rollers 94, 94M and 95 and the toroidal raceways of races 90, 9| and 92. It will be remembered that shaft 35 and race 92 are capable of slight relative axial movement to permit variations of pressure or loading with respect to rollers and races.

In addition to the elastic force applied thru spring |4| to increase traction of the rollers on the raceways, Fig. 1 shows torque sensitive means to vary the pressure between races and rollers in response to variations of thetorque load upon the propeller shaft. Said torque sensitive means comprises rollers interposed between pairs of reversely inclined surfaces on the rear face of race 92 and corresponding pairs of inclined surfaces in the forward face of a hard spacing collar |50, sleeved on hub |32 of abutment collar |3| and disposed between said collar and the forward face of the described universal joint yoke 40, which, it will be remembered, is capable of limited rotation with respect to the shaft 35 and nut 38. Spacing collar |50, on its rearward face, and universal joint yoke 60 on its forward end or face, are mutually provided with interlocking tongues and grooves, indicated by numeral whereby said yoke and spacing collar are compelled to rotate exactly in unison, that is, any rotative movement of collar |50 is imparted to yoke 60 or vice versa. The said inclined surfaces on the rear face of race 92 are indicated by numeral |52 and the cooperating surfaces on the forward face of spacing collar |50 by numeral |53. Between surfaces |52. and |53 one or more torque loading rollers |56 of barrel shape are interposed. These inclined faces may be arranged to present, when viewed in the direction of the axis of roller |56, shallow V-shaped lines, with the openings of the Vs opposed. The construction and arrangement of the barrel-shaped roller and the inclined plane or cam surfaces with which it is in contact is similar to those disclosed in patent to Erban 1,683,715. It is not necessary to form roller |56 in the contour of a complete barrel since the inner end of a complete barrel rollerpositioned as illustrated in Fig. l, would have no bearing on the inclined surfaces, therefore roller |54 has been illustrated as a half or slightly .larger fragment of a barrel-shaped roller severed on a transverse plane adjacent the longitudinal center. Roller |56 is held in an opening |55 thru spring abutment collar IBI, which, therefore, serves as a roller positioning cage. There may be a plurality of rollers and cam surfaces equiangularly spaced. If the load on the propeller shaft (yoke Q0) is the normal load for which spring IBI has been adjusted, roller |56 bears in the bottoms of the V notches formed on race 92 and spacing collar |50, and yoke 60 and propeller shaft coupled to it may rotate without angular displacement of spacing collar with respect to race 92. If higher loads are applied to the propeller sha'ft the spacing collar will yield angularly and in so yielding will force roller |54 in,

to move axially toward one another and clamp the intermediate rollers With greater force between the center and end races. Torque applied from the engine to race 92 is delivered therefrom to shaft 35 thru abutment collar |3| and thru torque loading rollers |54 to spacer collar |50 and thence to coupling yoke 40 and the propeller shaft. Thus, yoke 40 and spacing collar |50 together constitute a thrust receiving means between shaft 35 and race 92.

The races, the means for mounting them and for transmitting engine torque thru them to the l as to maintain the roller centers at definite radial l distances from the main axis of the transmission, permit the rollers to tilt for the purpose of changing the speed ratio and automatically equalize the torque transmitted by the two sets of roll'- ers and by the several rollers of each set. These means, among others as yet not specifically mentioned, will now be described.

A tube capable of endwise movement surrounds shaft 35. At each end ofthe tube is a set of radiating roller supporting arms movable endwise with the tube but capable of moving 'transversely of the shaft axis. The tube may be incapable of transverse movement while the sets of roller supporting arms may be immovable with respect to it axially and angularly although movable transversely of it a limited extent. Or the arms may be rigid with the tube in all respects in case the tube is constructed and arranged to move transversely of the shaft axis-as well as longitudinally thereof. In the embodiment illustrated, each of the rearward set of threerollers (94M and 94|) is positioned by one of three spider arms |60 radiating from a floating tube |6| which surrounds output shaft 35 and passes thru the sleeve H0 on which center race 90 has rotative bearing. Each of the forward set of three rollers 95 is positioned by one of three spider arms |62 radiating from and integral with a hub |63 which is sleeved over and keyed to the forward end of tube |6|. Hub |63 is held firmly against a shoulder on tube |6| by a locking nut |63a. As indicated in Fig. 1, arms |66 and |62 have their radial center lines substantially in the same axial planes. The floating tube 16| and radiating armsl66 and |62 form a substantially rigid unit. This floating unit is prevented from rotating with respect to the housing by two elastic arms |66 (Fig. 9) which are integral or otherwise rigidly connected to tube |6| in the same transverse plane as radiating spiderarms |60, and arch oppositely somewhat upward (to clear rollers 94) and laterally outward to terminate in preferably spheroidal bearing ends |65 which project into bearing chambers provided at opposite sides of the housing as illustrated in Fig. 9. roidal ends |65 of the two arms |66 are each held between upper and lower bearing blocks |66, each of which has a rounded cavity engaging said spheroidal end. Each bearing block |66 is backed by a supporting block |61 clamped or otherwise firmly attached to the housing. Between blocks |66 and |61 are ball bearing assemblies |68, the balls being suitably spacedy in centrally perforated disk-like cages |69. A pin |10 having three spaced fiangesextends into each block |66 and |61 and thru the central perforation in each cage |69, the central flange of the pin |10 occupying the center of the perforation thru the cage and the end flanges occupying the perforavtions respectively in the blocks |66 and |61 thus permitting lateral movement of block |66 and bearing balls. The pins may rock about the center flange to allow slight relative displace- The sphetube |6| and its spider arms in a fore and aft diment of the blocks and cage and yet prevent entire separation. The described bearings for the ends of arms |64 permit free movement to a small extent of the arms and the tube |6| substantially in a plane including the main axis and the centers of the spherical ends |65 of 4said arms and in planesparallel thereto, but check any rotating movement of the tube and arms around the main axis. AAdjustable stop pins may be adjusted to limit the extent of horizontal transverse movement of the arms |64. The inside diameter of tube |6| is substantially greater than the diameter of shaft 35 thruout the length of the tube and its exterior diameter is smaller than the internal diameterof bearing sleeve (see Fig. 1) thereby permitting bodily movement of the tube and attached spider arms sideways in the planes described. As arms |64 are purposely made elastic, tube |6| and attached spider arms may also move in a plane perpendicular to said plane that includes the main axis and the centers of spheroidal terminals |65. Therefore, tube |6| and attached spider arms have the capacity of oating or moving slideways as a unitin any direction a limited extent. Reference to Fig. 1 shows that said fioating unit has also a capacity for limited endwise movement, being centered longitudinally by springs and damping devices. Figs. 1 and 9 show also springs and damping devices for centering said unit transversely.

The means referred to for centering floating rection comprises expansion coil springs |80 and damping devices consisting of cylinders |8| and pistons |82 between which springs |80 react. (See Fig. l.) Cylinders 8| bear against races 9| and 92 while pistons |82 bear against sealing rings |83 between said pistons and the ends of tube I6|. The rear end of tube |6|is yieldably held properly spaced from shaft 35 vertically (considering the normal position of the transmission) by the elastic arms |64 hitherto described. The tube is also elastically spaced laterally from shaft35 by means of five coiled springs, and damping' devices two of which are opposed at the rear end of the tube as illustrated in Fig. 9 and` three spaced evenly around the front end of the tube, one of which is shown in section in Fig. 1 At its rearward end tube |6| is drilled in the plane of spider arms |60 to form two cylindrical bores |84 (one of which is shown in section in Fig. 9) in communication with the space between the tube and shaft 35. The outer end of each. bore is closed by a plug |85. Within each cylinder bore a piston is urged by a coiled expansion spring against shaft 35. The construction of the several laterally acting spring and damping devices, at each end of tube |6| will be more specifically described presently by reference to one of the centering devices adjacent the front end illustrated in Fig. 1. By means of,elastic arms |64 and opposed spring and damping devices within the cylinders indi-v cated by |84, the rear end of tube |6| is yieldably centered laterally, that is, with respect to the axis of shaft 35, and may move in any direction in a transverse plane to a limited extent against the opposition of the elastic' armsfcoil springs and damping devices described.

The forward end of tube |6| is centered with respect to the axis of shaft 35 by three damped elastic devices equi-angularly disposed. One of said centering devices at the forward end is illustrated in section in Fig. l. It comprisesv a boss |90, which may be integral with the structure composing the spider arms |62 and hub |63, disposed midway between two of said arms |62. Boss |90 is drilled radially to form a cylindrical chamber or cylinder bore |9| within which is a hollow piston |92 provided with a reduced extension |93 which enters a hole in tube |6| and bears against shaft 35. Extension |93 is perforated so that the interior of the hollow piston is in communication with the annular space between tube |6| and shaft 35. Outer end of cylinder bore |9| is closed by a threaded plug |94 having a guiding extension |95 over which the hollow piston slides. Coiled expansion spring |96 surrounds the piston between plug |94 and an exterior flange on the piston, thus elastically urging the piston against shaft 35. The other damped elastic centering devices, at the front end of tube |6| .are of similar construction. I

Front end of said floating unit is, therefore, centered with respect to shaft 35, by three symmetrically disposed damped spring devices, the rear end by two damped spring devices and the elastic arms |64, while said unit is held in normal position longitudinally by damped spring devices at` opposite ends. Thus the tube |6| and its attached spider arms as a unit maybe considered as floating in such manner that the unit may movesomewhat if subjected to unbalanced forces.

Thedntermediate friction rollers are shown in the drawings with their center planes parallel with the mainaxis and their axes of rotation lying in axial planes and, therefore, tracking on equal circles on the raceways so that races 9| and 92 rotate at the same speedA as race 90 but oppositely. The rollers are mounted, however, so that they may be tilted into a position wherein their center planes are oblique 'to themain axis and therefore cause the races 9| and 92 to rotate at a different speed from that of race 90. The mountings of the rollers which render them susceptible to external control and permit them to tiltV in order to change the speed ratio of the transmis- '1 and 9) as positioned on that one of the three arms |60 that extends toward the upper side of the housing and as constituting one of the rearward set of rollers as hereinbeforestated.

Rollers 94 constituting the other two of the rear- Wardv set are mounted respectively on the two other arms |60. 'I'he three rollers 95 composing the forward set are mounted respectively on three arms |62, only one qt which appears in Fig. 1, but which are equally spaced, as previously stated, the same as the arms |60 shown in Fig. 9 so that the .centers ofA the rollers of one set are intersected by the same axial planes as the corresponding rollers of the other set. The mountings of rollers 95 on arms -|62 are identical in structure, each with the others. The mountings of the two `rollers 94 on arms |60 are identical, one with the other. The mountings of rollers 94 differ from the mountings of rollers 95 only in that the sense of slant of the spacing blocks 205 (to be presently described) of the rollers of one set is necessarily opposite the sense of slant of the spacing blocks of the other set (Figs. 2 and 11), since the two sets engage opposite faces of the center race to deliver torque to or from races I and 92 in the same sense of rotation which fis, of course, opposite to that of race 90. A description of the roller mounting including journal bearing and associated parts of one of the rollers 94 or 95 will therefore suillce for all of the controlled or non-master rollers.

The end of each spider `arm |60, 1 62, is expanded into a bearing seat rounded in an axial plane including the main axis, and flattened on opposite sides parallel to said plane, as indicated at 200, (Figs. 1, 2, 10 and 11). Each rounded seat is perforated to receive a hollow pin 20|, normal to said axial plane said 'pin being-fixed by a set screw 201. The reaction forces of the rollers are transmitted to bearing seats 200. Each controlled follower or roller is so fitted on journal piece 202 as to be rotatable upon the external cylindrical bearing surface of the latter. Piece 202 is slotted longitudinally of its axis as at 203 (Fig. 2), the sides of the slot being parallel planes but having transverse grooves or key ways 204. Blocks 205, having opposite plane. surfaces oblique to one another, each provided with a transverse rib or key 206 (Fig. 2) engageable in the grooves or key ways 204 of the journal piece, are interposed between the bearing surfaces of bearing seat 200, and the opposed parallel walls of the slot 203, the keys 205 of said blocks engaging the grooves 204 of the journal piece. The

ends of said pins 20| which pass thru perfora' tions in the seats 200 of the spider arms enter holes in said blocks 205. By means of this construction each roller (94 or 95) is free to rotate on'journal piece 202 in order to transmit'torque; each of said rollers may tilt around the axis of pin 20| in order to change the paths of contact of its perimeter with the driving and driven races to change the speed ratio of the transmission; and tube |6l, each arm(|60, |62) ,bearing seat 200 and spacing block 205 mayA move in a direction f parallel with the main axis and relatively to the controlled rollers 94, 95, and journal piece 202, which are held between the raceways, thus tending to move eachroller in a direction resulting in displacing its axis of rotation out of the axial planes that includes the main axis and the roller center in which said axis of rotation lies normally, that is, when the forces acting upon the roller are balanced and the roller tracks in circles on the raceways. The effect of displacing the axis of rotation of a roller out of said axial plane ls to bring unbalanced forces to bear upon the perimeter of the roller which cause said roller to track in a spiral on the raceways and thus change the speed ratio position, as disclosed for example in patent to Spencer #751,958. The rollers are considered to be rotating in their normal planes of rotation when their axes of rotation lie in axial planes including the main axis and the roller centers and, necessarily, the center planes of the rollers are perpendicular to said axial planes, Whether or not parallel to the main axis. Said center planes are parallel of course to the main axis only when the transmission is in 1:1 ratio.

Control or master roller 94M is mounted on the bearing seat 200 of that arm |90 which supports it by means somewhat different from the means Whereon the controlled or follower rollers are lmounted, as illustrated in Figs. 1, 2, 9 and 10.

Like the bearing seats for the controlled rollers, the bearing seat 200 for the master roller is provided with a central perforation in which a hclow pin 20| is similarly secured. A journal piece 202M, on which roller 94M is mounted so as to rotate freely about its axis, is slotted similarly to journal pieces 202, but the walls of the slot are formed with transverse parti-cylindrical grooves 2|0, (Fig. 10) in which parti-cylindrical blocks 2|| fit. Said blocks 2|| are segments cut from a cylinder on planes oblique to the axis. The ends of pin 20| enter holes 2|2 in the particylindrical blocks 2`|| thus limiting the movements of said blocks to a tilting movement around the pin in an axial plane including the main axis of the transmission. Some clearance exists between the walls of the slot in journal piece 202M and thefaces of bearing seat 200 on arm |60. When the journal piece 202M is assembled with the blocks 2| the outer surfaces of the blocks lie in the same cylindrical surface and constitute a bearing on which the master roller and journal piece may be inclined in a plane transverse of the main axis about a line connecting the points of contact of the roller With the raceways so as to displace the axis of rotation of the roller out of the plane that includes the main axis and roller center for the purpose of causing said master roller to assume a different speed-ratio position. Because the flat faces of blocks 2| the outer cylindrical surfaces of which constitute a bearing on which the roller 94M turns while being inclined, bear upon the flat surfaces of seat 200 of arm |60, and are oblique to the axisof the complete cylinder of which the blocks are segments, longitudinal movement of floating tube |6| may displace the axis. of rotation of control roller 94M ina manner similar'to that in which the axes of rotation of the controlled rollers are displaced by axial movement of said tube.

Whenever the control or master roller 94M changes its speed-ratio position' the controlled rollers 9d and `95 automatically assume a corresponding speed ratio position, each assuming its proportionate share of the load. Consequently by changing the position of roller 95M in response to forces applied by the operator or a governor mechanism or both, the controlled rollers assume corresponding positions.

Means whereby the control or master roller may be adjusted to different speed-ratio positions will now be described:

On the radially outer end or top of journal piece 202M there is a parallel-sided flat-topped ridge or land 2|5 the outer face of vwhich is substantially parallel with the center plane of roller 90M and the sides or edges parallel with the axis t-t. A hole RIG extends thru journal piece 202M and said land 2|5, to receive a bolt 2H, to the opposite ends of which a control yoke 2|@ is pivoted by means of pivot holes 2|8A as shown in Figs. 1, 2, and 9. A hole 2|!) alined with the axis of journal piece 202M receives a stop pin 220 projecting upward into a wider notclrbetween two projections 22| on the inner or free end of the upper arm of control yoke 2|8. Another hole 222 is adapted to receive a screw 223 for securing to the land 215 a bridge piece 222 integral with two spring arms 225 which extend alongside the land 2|5, their ends turning toward each other beyond the end of the land'. The end of land 2|5 toward the outer end of yoke 2|8 (the right as shown in Fig. 9) overhangs journal piece 202M as shown and is curved as indicated at 226 (Fig. 3) on a center a eccentric to the center bs around which the control yoke 2|8 rocks in its limited angular movement. The maximum eccentricity is along the centerline of landl2l5. A friction pad 221 on the inside of lower limb of yoke 2|8, which may be integral therewith as shown in Figs. 9 and 10, rests against the lower face of the roller 94M. Another friction pad 22B which may be of metal,` made separate from the yoke, is disposed between the inside of the upper arm of yoke 2|8 and the .light upon the han, which transmits this light upper` face of the roller SIM as shown in Fig. 9.

Friction pad 228 is notched at the end more distant from the roller center at 229 to receive a pin 23|! projecting downward from said upper arm of the control lyoke, the width of the notch being greater than the diameter of the pin. The inner end of pad 228 has 'a reentrant curve 23| bearing againstthe curved end 226 of land 2I5, and is provided with two limiting pins 232 rising from its upper surface adjacent the ends of the reentrant curve. Pins 232 do not rise high enough to touch spring arms 225 during any angular movement of control yoke ZIB. As shown in Figs. 9 and 10 upper arm of yoke 2i8 is jogged upward at 233 on an incline which is curved on the said center b (Fig. 3) with its concavity opposed to the curved end 22S of land `2I5 and spaced therefrom suiiiciently to accommodate a ball 23e as of hardened steel which rests upon friction pad 229 between the ends oi' spring arms 225 and limiting pins 232. Upper arm of control yoke 2id bears down elastically upon ball 236i. The elastic pressure of this arm upon the ball may be regulated by means of the nuts 235 on the upper end of bolt 2W. Outer end of control yoke 2i8 at the junction of its arms is provided with a plate 236 elongated transversely of the arm and said plate has x'ed centrally to it a hard spherical bearing 231i for receiving the pressure exerted by an actuating lever operated by some external controlling or governing means. Said plate has opposite parallel surfaces and the mid-plane between said surfaces lies in the mid-plane of roller 95M and of course includes a line formed by the intersection of the mid-plane of the roller with a plane normal to the main ams of the transmission mechanism and including the roller center; said line is represented by the line t-t in Fig. 9.

V'I'he spherical bearing 23'@ maybe a steel ball pressed into a hole through the plate 235 leaving opposite segments of the ball protruding as bosses on oppmte sides of the plate.

When race 95B is being rotated clockwise (as viewed from the left of Figs. l and 2) to drive the car forward, roller @thi-as viewed in Fig. 2- is being rotated counter clockwise. The friction between pads 221, 22d and the roller tends to move control yoke 2id in the direction of rotation of said roller until further movement of said yoke in that'direction is stopped by stop pin 229 with control arm slanted toward the driving race as shown in Fig. 2. When race 99 is being rotated counter clockwise, as for backing a car, the roller 94M of course'rotatesl clockwise (viewed from the same view point) and tends to swing control yoke 268 in the oppositedirection until again stopped by stop pin 22e. So said yoke is slanted to one side orthe other of the axis represented by line t-t depending upon the directionof rotation of the roller.

When control arm 2|8 occupies a position at one limit or the other of its angular range of movementdue to the rotation of roller 94M about its axis' of power transmitting rotation, the pressure exerted by pad 228 against miler Mis intended to be rather light inorder to avoid excessive wear and substantial obstruction to the pressure to pad 228. Right hand end wall of notchV 229 of the pad bears against the stop pin 230, right hand pin 232 bears against the side of the ball 234, and Aleft hand spring 225 is slightly tensioned by the pressure of the ball. Should now the reverse train be coupled roller 94M will start to revolve clockwise. Then the frictionai I contact of the pads tends to swing control yoke 2I8 over to the right of the axis t-t (as viewed vin Fig. 2). Left hand spring 225 tends to push ball 234 -to the right into rmer'contact with the lefthandend of notch 229 contacts with pin 230 and the ball is by these tendencies caused to press with greater force downward upon the pad 22B. Due to the increased frictional contact of pad and roller thus effected, the roller carries the control yoke past the axis t-t until said yoke reaches the limit of its rangeof movement toward race 92 and is stopped by pin 220 with the right hand spring 225 tensioned by the ball and the left hand pin 232 bearing against the other side of the ball. The frictional pressure of pad 228 against the roller 94M is again lightened in this position as it was in the corresponding position at the other side 'of the axis t--t. f

Assuming that the forward train is coupled and engine running, control yoke Ri will be in posi. tion as shown in Fig. 2, with bearing sphere 231 son plate 236of control yoke 2l8 displaced with respect to the axis t-t of roller 94M, into that quadrant oi the circle of rotation of the roller tread in which the tread is approaching race 90. Now in order to reduce the speed ratio, that is, lower the rate of speed of the driven races 9| and 92 with respect to the rate of speed of the driving race 99, the roller 94M must be inclined to displace its axis of rotation out of the axial plane in which it normally lies, in a direction to cause the tread oi said roller to track on a contracting spiral on race 90 and on an expanding spiral. on race 92, so that the roller tilts. -Roller 94M may be inclined by pressing downward on the spherical bearing 23? as the mechanism is viewed in' Fig. 2.

This pressure will incline the roller about an axis center in a direction toward the left side of the housing as viewed in Fig. 9. In order that the roher may continue to transmit rotation at an even rate it is clear that the axis of rotation must lie in the axial plane that includes the roller center and, as a. corollary, that the center plane of the roller must be perpendicular to that axial plane whatever the angle ofthe roller may be with respect to the main axis.` In the 1:1 ratio position illustrated, of course, the, center plane of the roller is parallel with the main axis -and normal to said axial plane. If the ratio position is other than 1:1, the center plane' will still be normal to said axial plane but at an oblique angle to the main axis, and of course in either A"1:1

will lie in said axial plane. 'Under these conditions the active and reactive forces applied to the roller by the driving and driven'races Iare so balanced that they tend to maintain the central plane oi' the roller normal to and-its 'axis of roor any other ratio the axis of rotation of the roller` tation in, said axial piane.- when roner unas '7'5 been inclined as described so as to displace its. axis of rotation out of said axial plane and its central plane of rotation out of perpendicular with respect to said axial plane, it immediately begins to tilt, that is, to move angularly so that its plane of rotation changes with respect to the main axis. It is, therefore, necessary, when the desired degree of tilt has been reached that the axis of rotation of the roller and its plane of rotation be restored respectively into said axial plane and said plane normal thereto. Restoration is accomplished automatically by ceasing t press further against the bearing 231 and holding that bearing stationary until the plane of rotation, now held so that it tilts around an axis determined by the center of spherical bearing 231 and the roller center, again coincides with a plane normal `to said axial plane and the axis of rotation o f the roller again lies in said axial` plane. When reverse train is coupled it is obviously necessary in order to vary the speed ratio to apply force to bearing 231 on the other side of axis t-t in the approaching quadrant between said axis and point of tractive contact a. controlling element in the form of a bell crank 4 lever is provided as illustrated in Figs. 2, '4, and 9. Said bell crank lever comprises a rock shaft A240 having bearing in a bushing 24| within a detachable bearing bracket 242 secured within the housing, a bifurcated power arm243 keyed to the outer end of said rock shaft and a double acting work arm 244 consisting of a slotted member extending transversely of and integral with or otherwise rigidly united centrally of its length to the inner end of the rock shaft. Rock shaft 240 and work arm 244 of the bell crank lever have the' contour of the letter T as may be seen in Fig. 2, the slot 245 in the work arm trending fore and aft when the 1:1 ratio prevails. Plate 238 lies within slot 245 which is Just wide enough to receive the spherical bearing contact member 231, but so that there may be sliding motion between .said member and the sides of the slot. Adjustable stop pins 246 are disposed in the double acting work arm 244. two opposed one to the other on' opposite sides of the axis'of the rock shaft as indicated in Fig. 2 and 9.- One end or the' other of plate 236 on control yoke lies between the inner ends of said pins as shown in Fig. 13. The axis of said rock shaft extends parallel with the line `tt (Figs. 2 and 9), and is preferably offset slightlyv therefrom for a purpose to be hereafter stated. In Fig. 13 the adjacent arrow-pointsat i indicate thisoil'set relation which in the illusi trated embodiment, is in a horizontal plane which is a` plane coincident with the central plane of roller 94Mwhen the. latter is in 1:1 ratio position.

Whenfthedrive is in a forward direction, control arm; 2li. slanted toward driving race ligand spherical' bearing member 231 disposed in ,the

' approachirig? quadrant of rollerfMM; if; rock shaft. 240 be', rotated in a clockwisesense, viewed from the'outerv end of'the rock shaft (the right `of Fig. 9 andthe top of Fig. 2)-, the platen 23| ,will be depressed (from the point of view of Fig. 2l by reason of pressure applied to bearing member 231 and control yoke, Journalpiece and roller inclined out of the normal plane of rotation in a one of the stop pins 246, as indicated by the diagrams Figs. 13, 13a and 13b. The amount of rotation of the rock shaft is thus limited by the movement of the plate 236 within the slot 245, since the control arm and plate are rigid torsionally and the heavy pressure of the races upon the tread of the roller tends strongly to prevent the latter from sliding radially on the races to a new ratio position by any force applied to the rock shaft tending to rotate said plate about the tilt axis of the roller. 'Ihe amount of inclination,

therefore, that can be imparted to the roller preliminary to the assumption by the roller of a new ratio position is limited by the amount of clearance between the plate 235 and the sides of the slot as represented by the adjustable stop pins. So it is not possible to change ratio position too rapidly. In changing to a higher ratio of output to input speed -rock shaft 240 would be rotated in the opposite sense (counter-clockwise viewed from the outer end of the rock shaft).

When the drive is in reverse control yoke 2| 3 assumes a position in the quadrant of rotation approaching race 92 or, looking at Fig. 2, a slanting position to the right of the axis t-t. Arm 244 on the opposite side of the axis of rock shaft 240, from that which operated on the control yoke 2l8 during'forward drive, now engages spherical bearing member 231. The same movements of the rock shaft 240 that determined the assumption of low and high speed ratio positions by roller 94M in forward drive now determine theassumption of low and high speed ratios in reverse drive.

If the axis of rock shaft 240 coincided with the axis t-t of roller 94M when rotating in its normal plane, proper movement of said rock shaft would impart equal angles of inclination of the roller from.the normal plane of rotation in all tilt positions of the roller so that the rate of speed -ratio change would be the same when shifting from any speed ratio or tilt position. It is desirable,- however, that the rate of speedratio change vary in accordance with tilt or .ratio position and the direction or sense of change from that position. In order to obtain this variable rate of speed-ratio change the axis c-,c of rock shaft e 240 has been offset from the axis t-t when the roller is in its normal plane of rotation as shown in Figure 13. Owing to the different positions of the centers around which the roller 94M tilts andthe rock shaft 240 rocks, the workarm 2 44 of the rock shaftassumes different angularvpositions with respect to the plane of rotation of the roller in its different tilt positions and therefore oflthe plate 238 which includes said plane of rotationr' By vreference to Fig. 13 it will be seen that in the 1:1 ratio position of the roller, work arm 244 lies parallel with plate 236, if the axis of rotation Aof rock shaft 240 lies in the normal plane of rotation of the roller when in 1:1 ratio position as shown. If, now, the rock shaft be rotated clockwise around its center of rotation c a .limited inclining movementwill be imparted to an increasingly greater angle with respect to the plane of plate 236 thus allowing an increasingly greater extent of inclining movement of said plate, and therefore of the roller, so that as the roller tilts to lower speed ratio positions (Fig. 13a) the rate of tilting increases. In proceeding from low-speed ratio positions toward 1:1 ratio, the successive inclining impulses cause progres- ,sively lesser amplitudes of inclining movements of the plate, control arm and roller until 1:1 ratio position is attained. In going into over drive, that is, proceeding from 1:1 ratio position shown in, the diagram, Fig. 13, toward the higher-speed vof the axis or center of rotation c of the rock shaft that is a different distance from the center of spherical bearing 231 than is the center or axis of tilt represented by t will cause variations in the rate of tilt from a higher to a lower speed ratio position or vice versa. And the relations of thse two centers may be readily chosen so as to effect the desired results. As external force for operating the rock shaft 240 andwork arm 2.44 is applied by means of an elastic link or equivalent compensating device between it andthe governor, as hereinafter described, the latter may set the limit of ratio change required for a given engine speed, while the work arm 244 by reason of the described construction and relationship to the plate 236 will limit the rate of inclination of the roller.

Forked power arm 243 keyed to the outer end of rock shaft 266 receives the rear endoi an elastic link between its limbs to which the link is pivoted by a pin 231 held iny place by a plate 248 secured to shaft 240 by nut 249. The other end of said elastic link is connected by appropriate link and lever mechanism to a centrifugal governor, a manual control means and a damping de- `vice, all to be presently described. The connections and devices referred to will be considered, proceeding toward the governor and manual control from the power arm 243 of the bell crank lever that directly imparts inclination to the master roller 94M and initiates conditions for producing ratio change. f

Said elastic link (Fig. 4) comprises a fitting 254 pivoted to arm 263 by pin 241; a rod section 25| screw connected to the fitting, said rod section having an enlargement 252; a tubular sleeve 253 within which -rod section 25| may slide telescopically,` beingguided therein by a smoothly perforated plug 259 secured in one end of the sleeve, and the`- enlargement 252 sliding in a bearing surface within the sleeve; a second rod section 254 adjustablyv threaded into a plug 255 secured in the other end of the sleeve 253; pre-loaded or compressed coiled expansion springs 263 interposed between washers resting against the ends ofthe enlargement 252 of rod section. 26| and the plugs at the ends of the sleeve, and a fitting 251 connected to rod section 254 pivoted at 258 to the longer arm 26B of a bell crank lever, fulcrumed at 26| to arms 262 on a balanced rockable member 263, which is provided at each end with shaft extensions 266, 264a (Fig. 2) turning in bearings in the housing. The fulcrum 26| of said bell crank lever consists of afpintle rod 269, secured to and extending between said arms 262. The bell crank bell comprises a sleeve 265 surrounding'pintle rod 269 asshown in Fig. 2, to

which sleeve, nearA one end, arm 260 is integrally or otherwise rigidly united. Two shorter arms 266 and 261 have forked ends engaging pins 268 projecting from diametrically opposite points on a ring 306 sleeved in a groove in a governor controlled sleeve 210.

In the illustrated embodiment sleeve 210 (Fig. 5) surrounds an upright shaft 21| perforated throughout its length, as at 212. The lower end of shaft 21| is supported in a step bearing 213 in the housing, while a stud 2 14 depending from the housing enters a counter bore 215 in the upper end of the shaft. Beneath the counter bore 215 is a smaller counter bore2'l6 receiving a coil spring 211 which presses against a ball 218 dis- `posed in counter bore 215, tending to press said ball upward against the lower end of 'stud 214 (which has a conical seat therein) and said shaft downward. 'Ihe upper end of shaft 21| is somewhat enlarged and has rigid with it diametrically opposite pairs of spaced ears 219, between which are pivoted lever arms 280 having ball weights 26| at their outer ends. Said lever arms are fulcrumed at 282, and have their inner or work arms 283 formed with curved cam-like lower surfaces bearing upon the snooth top of sleeve 210. Stops 283a limit the upward swing of arms 283. Shaft 21| carries an adjustable spring abutment collar 284. Surrounding shaft 21| above the abutment collar is a coiled spring '285; surrounding the shaft 21| above the spring 285, is a slidable collar 286 pressed upward by the spring against a shoulder 281 on the shaft.

Above the collar 286 is another coiled spring 288,

surrounding said shaft and pressing against collar 286 and an internal flange formed at the upper end of sleeve 210. 'I'his sleeve is drilled and counter-bored to afford a nicely fitted bearing for the sleeve to slide on the shaft and on the collar 286, and providing space between the shaft and sleeve for said springs. An internal shoulder 289 within the sleeve is adapted to engage collar 286 after a given extent of downward sliding movement of the sleeve. The resistance of spring 288 to compression is less than that of spring 285 so that after contact of shoulder 289 with collar 286 resistance to downward movement of the sleeve is increased. Adjacent its lower end a helical tooth pinion 290 is fixed to shaft 21| with its lower face resting against the flange of a flanged bushing which lines the step bearing 213. Helical gear 29| rotatable on fixed shaft 65 meshes with said spiral pinion 298. Gear 29| is integral or otherwise xedly joined to spur gear 64, which, it will be remembered, is

the reverse idler gear always in mesh with gear 66 fixed to shaft 32. From the described construction and arrangement of the governorand the link and lever connections therefrom to the described control yoke 2|8, the position of which determines the speed ratio position of said master roller 94M, it will be perceived that increasi118 Speed of input shaft 32 causes the centrifuf gal forces exerted by the governor balls to move governor sleeve 219 downward thereby rocking link connected arms 260 and 243 counter clockwise (viewed from the right hand side of the transmission housing-i. e. from the top of Fig. 2, front of Fig. 4, and right hand side of Fig. A9) Counter clockwise rotation of rock shaft 240 to which arm 243 is keyed, it will be remembered; imparts an inclination to roller 94M in such a manner as to initiate a tilting movement thereof to a higher-speed ratio position, that is, roller 94M tracksin an expanding spiral on driving race 90 and a contracting spiral on driven race 92.

Hence, increasing speed of input shaft tends, thru the governor, to adjust the master roller to a high-speed ratio position, and, reversely, decreasing speed of the input shaft tends to effect adjustment of the master roller to a lower speed ratio position.

Shaft extension 264a of rocking member 263 protrudes thru the housing H and to the protruding end of said shaft extension an arm 292 is i'lxed. Arm 292 is connected to external control means (not shown) under manual control of the operator.

On member 263, which may be rocked by external force applied to arm 292, are two short lugs or arms 293 of substantially the length of arms 262, before described, projecting from the opposite side, however, of said member. Between said lugs one end of a link 294 is pivoted, the opposite end of said link being connected to the piston 295 of a dash pot disposed within the lower portion of compartment 22 of the housing where it is submerged in lubricating oil when the housing is properly supplied therewith. Said piston is ported as at 296 and the ports are normally closed by a check valve 291 elastically seated by a coiled spring 298 surrounding a central depend ing projection 299 provided with an abutment flange 399 between which and the valve the spring is confined. A by-pass 30| (Fig. 8) may be regulated in the usual manner by a needle or equivalent valve 362. Upward movement of the piston accompanying rocking of member 263 counterclockwise as viewed in Fig. 4, is relatively unresistedbecause the valve then opens; but downward movement of the piston accompanying clockwise rotation of member 263 is resisted bev cause in this direction of movement the valve is under pressure of the iiuid in the dash pot.

It will be perceived from inspection of Fig. 2 that manually operative arm 292 secured to the shaft 266e of rockable member 263 projects thru the right hand side of the transmission housing as viewed from the rear of the transmission. Hence,l if arm 292 be moved manually in a counter-clockwise sense of rotation (see Fig. 4) the `bell crank lever will fulcrum on pins 268, (movement of which is resisted by governor action) and upper end of arm 260 of said lever will move clockwise or-forward (to the right, Fig. 4) thereby imparting a clockwise movement, (thru the described elastic link connection) to arm 243, rock shaft 240', and lever Work arm 244, which, in the forward driving condition, it will be apparent, inclines master roller in' the sense which guides it to a lower speed ratio position. This movement toward low-speed ratio position is resisted only slightly by the dash pot resistance and may be rapid. Contrarily, if manual control arm 292 be rocked4 in a clockwise sense arm 260 will move counter-clockwise and cause rock shaft 240 to inlcline the master roller in a sense which guides it to a higher speed ratio position and the latter movement tends to be slow because in this direction the dash pot resistance is high. Ihe effect of rocking the manual control arm 292 when kthe transmission is in reverse will be the same as that described for forward drive since inclination control' yoke 2|8 shifts position automatically 'as described, when the races reverse.

J separates the sump from the main part of compartment 20 to remove the coarser solid impurities that may be in the oil as it flows into the sump from compartment-20. The bottom of the sump is formed by a sheet metal plate 3|| corrugated in a fore and aft direction as indicated in Figs. 1 and 5. Plate 3|| is bolted, oil tight, to the housing H against an interposed gasket 3|3 by bolts 3|2 and is provided with a drainage port closed by a screw plug 3|4.

In the lower portion of chamber 22 (Figs. 1 and 5) an oil pump is disposed in position to be submerged in oil when the housing has been charged with the normal quantity of lubricating oil. The oil pump shown is of the gear pump type comprising a pump casing 3|5 enclosing meshed oil impeller gears 3|6 and 3|1. Suitable intake and discharge ports (not shown) for oil, are provided in the casing according to conventional practice, the intake being suitably screened if required. A pressure chamber 3|8 communicates with the discharge or pressure port. Said pressure chamber is provided with a suitable relief port 3|9 which is kept closed by a spring urged valve 320 until abnormal pressure compels it against thei elastic pressure of the spring to open the port and allow oil to escape into the sump. Impeller member 3|6 of the pump is secured to a vertical shaft 32| to the upper end of which is keyed a helical driven gear 322 in constant mesh with a helical'driving gear 323 fixed to countershaft 6|. When main clutch shaft 30 is coupled to the engine and gear in neutral, the oil pump may be driven from the engine to force oil circulation before starting the car. Pressure chamber 3|6 is in communication .with two pipes or other oil conduits to conduct oil therefrom to the parts requiring to be lubricated by a forced feed of oil.

Oil pipe 330 leads from pressure chamber 3|8 to right angularly disposed communicating passages 33| and 332 drilled in the housing. A

radially disposed tube 333 has its radially outer in'iiuid tight communication with oil passageY 332 and the annular space between floating tube |6| and shaft 35. Thru the conduits and passages thus far described oil under pressure fills said annular space which is sealed at each end bythe described spring-enclosing dash pots which receive oil for damping purposes. Each spider arm |60, |62 is drilled radially as at 331 (Figs. 1 and 9)'. Oill under pressure, therefore, enters the passages in the spider arms and proceeds to the previously described bearingl elements for the power transmitting rollers mounted on their outer ends. From these radial passages in the spider arms oil enters thru lateral hole 338 (Fig.

-forward end of tube IBI.

10) into each hollow pin 20| from theA ends of which it flows to the surfaces between the bearing planes of the controlled-roller supporting spider arms and inclined blocks 205, and between said blocks and the parallel sides of the slot in said journal pieces 202. Oil distributing grooves may be formed in these surfaces if desired. In the bearing elements of the controlling or master roller the ow of oil is the same, remembering that here parti-cylindrical blocks 2|| take the place of the plane-sided `blocks 205 of thecontrolled roller bearings. The forward raceways are'lubricated and cooled by oil jets projected against them from oil jet tubes 340 (Fig. 1) communicating with one or more of the spring containing laterally acting dash pot cylinders utilized as lateral centering means for the Similar jetting devices may be applied to jet oil upon the opposite race- Way of race and upon the raceway of rear- .34| communicating with the space between tube IBI and shaft 35, and with jet orifices 342.

For the purpose of lubricating the governor shaft bearings and governor parts, oil is conducted from oil pressure chamber 3|8 thruy oil conducting pipe 350 (Fig. 5) to a passageway 35| drilled diagonally upward in the housing to step bearing '213 for the governor shaft. Oil under pressure therefore, enters the step bearing, passes upward thru the passage 212 drilled thru the governor shaft to ball 218 and stud 214 lubricating these. Some of the oil is forced out of the top of the governor shaft and ows outward over the top, downward between and over lugs 219 to oil the ball governor arms and pivots, and also down governnor shaft inside of the governor sleeie to lubricate the relatively sliding surfaces therein. y

Parts not receiving oil directlyfrom the pressure system described are lubricated by the oil spray and fog created by the movements of the rotating parts in the oil contained vin the housing, suitable oil holes being provided wherever needed to allowoil spattered onto external surfaces toV get to bearing surfaces within, as shown for example, in Fig. 2 where oil holes 352may be s'een in sleeve' 253 of the'elastic link connec-` tion and an oil hole 353 in bracket 242in which rock shaft 240 has bearing.

To put this transmission into operation selective gear set shift lever 8| (Fig. 5) should be so operated as to adjust the selective gear assembly in neutral, (that is when slidable clutch element 52 is disconnected from the prime mover shaft 30 and sliding gear 63 onfthe countershaft is out of mesh` with the 'reverse idler) and the engine started with the main or engine clutch open if such a clutch is used. The clutch may then be let in. Now no motion is `transmitted to the friction transmission unit. Theoil pump, however, being geared to the countershaft 6| starts and begins to circulate oil to the parts of the friction unit and governor. The governor, however, is idle since it is geared to the input 4shaft 32. The friction rollers are in low speed ratio position prior to starting having been so adjusted by the governor. To start the car forward, the-main clutch may be released in the usual manner, shift lever 8| manipulated so as to cause engagement of the jaw clutch elements 5| and 53, thereby coupling input shaft 32 to the engine. Upon permitting the main clutch to reengage said shaft 32 transmits its rotation (received from the engine) to the governor, and to race 90; the latter rotates rollers 94, 94M and 95, which in. turn rotate races 9| and 92 and thru the latter output shaft 35. Output shaft 35 transmits its rotations to the forked coupling 40 which has a lost motion driving connection therewith and transmits rotation to the load as for example, to the traction wheels of a car. Spring 4| provides the axial pressure between races and rollers necessary to produce adequate tractive engagement for light loads. As the load increases the forked coupling 40 yields angularly thereby transmitting an axial force thru the described torque loading devices to .race 92, thus increasing the pressure between races and rollers as the need therefor increases.

As engine speed increases the governor applies a yielding force to shaft 240 tending to rock it in a counterclockwise direction as viewed from vthe right of Fig. 9. As master` roller 94M is now rotating counterclockwise, as viewed in Fig. 2, control yoke 2|8 is in the advancing quadrant of roller 94M with respect to race 90, so that as the 'or transmits more of the load than the other rollers of the set, the rear end of sleeve |6| is displaced in adirection parallel to the plane of the torque forces tending to displace the roller axis, by reason of the pressure exerted by the master roller on its spider arm `in a direction tending to reduce its speed ratio. The displacement of the axes of rotation or centers of the other two rollers 94, as will be seen upon reference to diagram Fig. l2, is one-half as much as the displacement of master roller 94M due to overload (which is in a. direction to reduce speed ratio) and in directions which cause said rollers 94 to assume a higher speed ratio position, so that they will equalthe speed ratio position of theA master roller when restoration of its displaced axis has occurred. As .the speed ratios of the set of rollers 94M, 94 were being equalized, the speed ing become greater than that of the set of rollers f 95, floating tube |6|\ has been moved axially (toward the right as shown in the diagram Fig. 11) by the lateral pressure of the journal pieces 202 of the rollers 94M, 94, upon the inclined blocks described as located between the ends ofthe spider arms and the journal pieces; and this axial movement of the floating tube has imparted a lateral component to the rollers -and displaced their axes of rotation in a direction to induce them to tilt to a higher ratio position while the rollers 94M, 94, were being simultaneously moved to reduce their speed ratio until equality of load between the rollers of the two sets became established. Y 4

Similarly, if by chance any roller of either setA assumes or transmits more load than the others', equalization will take place by the vmeans described.

Referring again to Figs. 11 and 12, if roller axis of mation win be displaced in a downward 94M carries more than its share of theload,

direction as viewed in Fig. 11, if race rotates in the direction indicated by the arrow, or to the left as viewed in Fig. 12 (a diagram of the spider arms |60 as viewed from the right of Fig. 11), where n indicates thecenter of the master roller 94M and 'n.2 and 11.4 indicate the centers of rollers 94. The spider arms |60 being free to move transversely of the main axis of 7the transmission they will assume the positions indicated by dotted lines. The axis or center of roller 94M, represented by n, will have moved to n', while the axes of rollers 94 represented by n and n* will have been moved to n3 and 115 respectively. The axes of rollers 94 will have been moved lust one-half the distance of the movement of the axis of roller 94M as can be proven. Inspection of the diagram will show that the movement of the axis of roller 96M (n) is in a. direction that will bring about a reduction of speed ratio, while the direction of movement of the axes of rollers 9d (n2 and n4) is such as to bring about an increase of speed ratio, the total result effecting an equal distribution of load among the rollers 94M and St.

When any inequality of torque exists'between the set of rollers 94M, 95, and the set of rollers 95, equalization between the two sets is effected as has been described. But, referring'more speciilcally to `Fig. 11, and assuming race Soto be rotating in the direction indicated by the arrow,-if rollers 95, for example, transmit more torque than rollers 96M, 9d, the reaction of rollers will force the spider arms |62 and tube i6! endwise,to the left as viewed in said figure, by reason of the axial component produced by the inclined faces of blocks 295. This movement tends to displace the axes of rotation or centers of rollers 85 downward as viewed in Fig. 1l and the center of roller 94M, upward, as viewed in Fig. l1. Thus the displacement of the axes of the two sets of rollers will be equal and opposite, so that the rollers of both sets will tilt to new and similar ratio positions.

When master roller 94M has been inclined as described by a force applied thru rock lever 240, 244, upon control yoke 288, the roller begins to tilt to a new ratio position. Since the rock lever when rocked to the intermediate limit permitted holds the yoke in the inclined position at the point of contact between yoke and rock arm, the roller is forced to turn or tilt vfor the moment around a line joining the said point of contact with the roller center and this turning or tilting movement continues until the roller axis becomes restored to the radial plane including the main axis and the roller center, when the torque forces acting on the roller are balanced.

The spring devices illustrated as acting constantly upon the floating tube and spider arms tend to keep this unit in a central normal position endwise and laterally. Any force suddenly applied tending to displace the oating unit from its normal position is opposed by the dashpots described so that oscillations of this unit are damped.`

The control exercised by the governor over the master roller 94M being exercised thru an elastic link the movements imparted to the master roller to control its ratio position are not too sudden: and when thevshift is made manually toward high the dash pot illustrated in Figs. 4 and 8 checks too rapid movement. The control exercised manually thru arm 292 and rocking member 263 may be effected independently of the governor.

. A specic embodiment oi' the invention has alined powerinput and power output shafts; a

variable speed-ratio frictional power transmitting unit for rotating the power output shaft; means for driving the frictional power transmitting unit from the power input shaft; a selective gear power transmitting unit for driving the power input shaft; means for selectively coupling the power input shaft to the prime mover mechanism; means for lubricating the elements of the frictional power transmitting unit including a pump; a speed responsive governor, means controlled by the governor operative to vary the speed ratio of the frictional power transmitting unit; a driving element on the prime mover mechanism, driving connections therefrom to the pump, and driving connections from the selective gear power transmitting unit to the governor.

2. In frictional power transmitting mechanism, the combination of coaxial spaced apart races with toroidal raceways, intermediate tiltable rollers in tractive ,engagement with said raceways whereby torque may be transmitted from one race to the other, a floating roller support capable of movement transversely of the race axis and elastic means tending to hold said oating roller support in a normal centralized position. Y

3. A combination as dened in claim 2 in which Vthe elastic means consists of a plurality of elastic devices tending to hold said floatingroller support in the normal centralized position, said elastic devices being angularly spaced with respect to the directions of application offtheir elastic forces, and vibration damping means associated with said elastic devices.

4. A combination as defined in claim 2 associated with a shaft coaxialwith the races, a plurality` of elastic devices tending to hold said oating roller` support in the normal centralized position, said elastic devices comprising spring pressed plungers and dash pot cylinders enclosing said spring pressed plungers disposed on said roller support, the ends of said plungers bearing against the shaft.

5.` A combination as defined in claim 2, associated with a housing, transversely elastic arms on said oating support, and iioating bearings in said housing for receiving the ends of said arms.

6. A combination as defined in claim 2 in which the transversely floating support comprises three equally spaced arms radiating outward from the race axis, tiltable Journals on the ends of said arms on which the rollers rotate and with which they may tilt.

7. In frictional power transmitting mechanism, the combination of a shaft, two spaced apart races secured to said shaft soas to rotate therewith, an intermediate race coaxial-with said shaft and rotatable independently thereof, a bearing. sleeve for said intermediate race spaced from the rshaft, anendwise floating tube surrounding the shaft and passing thru said bearing sleeve, individual roller supports on each end of said tube.

tiltable rollers f n said supports and bearings for 

